What usually causes metabolic alkalosis in the body?

Metabolic alkalosis is characterized by an increase in the pH of body fluids due to the loss of hydrogen ions or an accumulation of bicarbonate. The correct answer is linked to the excessive loss of metabolic acids, which can occur through various mechanisms such as prolonged vomiting, excessive use of diuretics, or certain hormonal imbalances. When the body loses acidic components, the overall balance shifts towards alkalinity, resulting in metabolic alkalosis.

In the context of the other options, while excessive production of lactic acid (notably from anaerobic metabolism) typically leads to metabolic acidosis, increased CO2 retention usually contributes to respiratory acidosis rather than metabolic alkalosis. Increased levels of calcium, although they can have various physiological effects, are not a direct cause of metabolic alkalosis. Therefore, the significant factor leading to the condition is the excessive loss of metabolic acids, which effectively raises the body’s pH.